Purpose: To delineate the clinicopathologic features and biologic behavior of the diffuse sclerosing variant of papillary thyroid carcinoma (DSV-PTC) and to report its outcome.
Methods: The clinical records of 25 patients who had surgery for DSV-PTC from 2004 to 2017 were retrospectively analyzed. Comparisons were made to similar studies in the literature reporting ≥8 cases and a cohort of classical PTC.
Results: There were 20 females and 5 males with an average age of 23 years (range 10-39 years). Bilateral disease occurred in 80% of cases. The mean size of the dominant mass was 4.2 ± 1.92 cm. In 92% of cases, therapeutic neck dissection was performed. Male sex significantly correlated with a higher yield of positive lymphadenopathy (p = 0.045). 62% of patients had recurrent disease. Recurrence significantly correlated with male sex, the number of metastatic lymph nodes (cutoff: 22 lymph nodes), and multifocality (p = 0.044, p ˂ 0.008, p ˂ 0.003, respectively). However, it did not correlate with the age at presentation. No disease-specific mortality occurred after an average follow-up of 77 months (range 12-168 months). The two comparisons made demonstrated a statistically significant greater tendency of the current series of DSV-PTC toward more aggressive clinicopathologic features and biologic behavior. No differences in overall survival were observed.
Conclusion: The DSV-PTC should be considered a high-risk PTC that mandates an aggressive therapeutic strategy with the intent of optimizing disease-free survival.